Abstract: A heat-driven engine having a first, thermally conductive, pump to which a working medium is admitted and within which the working medium subsequently absorbs its latent heat while undergoing a phase change from low to high enthalpy phase before being expelled from the first pump. Also, a restrictive cooling element accepts the working medium in its high enthalpy phase and allows it to release its latent heat and undergo a phase change from a liquid to a low enthalpy phase. A first and a second passage, through which the working medium traverses, connects the first pump and the cooling element. The second passage incorporates a thermally conductive element, placing the working medium in thermal contact with a heat source or sink. Also, a heat pump is in thermal contact with the first pump and the cooling element. Finally, a power transmission element links the first pump to the heat pump.

Abstract: A heat-driven engine includes a thermally conductive path into the engine, from a heat source and a working medium of a thermostrictive material, having a first temperature of transformation, positioned adjacent to the thermally conductive path. Also, a heat pump of phase change material is positioned adjacent to the working medium and an actuator is controlled to apply stimulus to the heat pump, causing a phase change and an associated release of thermal energy, to drive the working medium above its low-to-high temperature of transformation and controlled to alternatingly remove the stimulus from the heat pump, causing the phase change to reverse, and an associated intake of thermal energy, to drive the working medium below its high-to-low temperature of transformation. Also, heat flow through the thermally conductive path maintains the working medium at a temperature range permitting the heat pump to drive the working medium temperature, in the manner noted.

Abstract: A method of cooling a first region that is above the transition temperature of a phase change material having a cold phase and a warm phase and that is proximal to a second region into which heat may be exhausted. The method utilizes an article of the phase change material, and starting in the cold phase, places the article into thermal contact with the first region, thereby causing the phase change material to undergo a phase transition, changing size. When the phase transition is substantially complete, the article is taken out of thermal contact with the first region and is placed into thermal contact with the second region. At this point, force is applied to the article, causing it to transition to the cold phase, thereby exhausting heat into the second region. The process is begun again, by placing the article, once again, into thermal contact with the first region.

Abstract: A heat-driven engine includes a thermally conductive input path, from a heat source and a working medium of a thermostrictive material positioned adjacent to the thermally conductive path. Also, a heat pump of phase change material is positioned adjacent to the working medium and an actuator is controlled to apply stimulus to the heat pump, causing a phase change and an associated release of thermal energy, to drive the working medium above its low-to-high temperature of transformation and controlled to alternatingly remove the stimulus from the heat pump, causing the phase change to reverse, and an associated intake of thermal energy, to drive the working medium below its high-to-low temperature of transformation. Also, heat flow through the thermally conductive path maintains the working medium at a temperature range permitting the heat pump to drive the working medium temperature, in the manner noted.

Abstract: A heat-driven engine includes a thermally conductive path into the engine, from a heat source and a working medium of a thermostrictive material, having a first temperature of transformation, positioned adjacent to the thermally conductive path. Also, a heat pump of phase change material is positioned adjacent to the working medium and an actuator is controlled to apply stimulus to the heat pump, causing a phase change and an associated release of thermal energy, to drive the working medium above its low-to-high temperature of transformation and controlled to alternatingly remove the stimulus from the heat pump, causing the phase change to reverse, and an associated intake of thermal energy, to drive the working medium below its high-to-low temperature of transformation. Also, heat flow through the thermally conductive path maintains the working medium at a temperature range permitting the heat pump to drive the working medium temperature, in the manner noted.

Abstract: A method of cooling a first region that is above the transition temperature of a phase change material having a cold phase and a warm phase and that is proximal to a second region into which heat may be exhausted. The method utilizes an article of the phase change material, and starting in the cold phase, places the article into thermal contact with the first region, thereby causing the phase change material to undergo a phase transition, changing size. When the phase transition is substantially complete, the article is taken out of thermal contact with the first region and is placed into thermal contact with the second region. At this point, force is applied to the article, causing it to transition to the cold phase, thereby exhausting heat into the second region. The process is begun again, by placing the article, once again, into thermal contact with the first region.

Abstract: A heat-driven engine includes a thermally conductive path into the engine, from a heat source and a working medium of a thermostrictive material, having a first temperature of transformation, positioned adjacent to the thermally conductive path. Also, a heat pump of phase change material is positioned adjacent to the working medium and an actuator is controlled to apply stimulus to the heat pump, causing a phase change and an associated release of thermal energy, to drive the working medium above its low-to-high temperature of transformation and controlled to alternatingly remove the stimulus from the heat pump, causing the phase change to reverse, and an associated intake of thermal energy, to drive the working medium below its high-to-low temperature of transformation. Also, heat flow through the thermally conductive path maintains the working medium at a temperature range permitting the heat pump to drive the working medium temperature, in the manner noted.

Abstract: A method of generating motion from a cool region that is proximal to a warm region, the cool region and the warm region defining a temperature range. The method uses an article of phase change material having a warm-to-cold phase transition and a cold-to-warm phase transition, both within the temperature range. This article is exposed to the cool region, thereby causing the phase change material to change size. When the warm-to-cold phase transition is substantially complete, this is detected. In response to this detection the article is exposed to the warm region, thereby causing the phase change material to change size. When this transition is substantially complete, the cycle is restarted with exposure to the cool region.